Lighting apparatus

ABSTRACT

A lighting apparatus includes a rectifier, a loading module and a current supplemental module. The rectifier is connected to an output of the AC power for receiving an AC signal. The rectifier converts the AC signal to a positive wave signal. The loading module is disposed at an output of the rectifier. The loading module includes multiple loading units connected in series. Output of each loading unit is connected to a current limit module. Each current limit module has a voltage conductive threshold and a working cycle dispatched to each current limit module according to the positive wave signal. The current supplemental module is connected to an output of the rectifier and an input of the loading module. The current supplemental module charges the current limit module during the working cycle and outputs current to the loading module when the positive wave signal is not sufficient to drive the loading module.

FIELD

The present invention is related to a lighting apparatus, and moreparticularly related to a lighting apparatus with a stable power input.

BACKGROUND

The time when the darkness is being lighten up by the light, human havenoticed the need of lighting up this planet. Light has become one of thenecessities we live with through the day and the night. During thedarkness after sunset, there is no natural light, and human have beenfinding ways to light up the darkness with artificial light. From atorch, candles to the light we have nowadays, the use of light have beenchanged through decades and the development of lighting continues on.

Early human found the control of fire which is a turning point of thehuman history. Fire provides light to bright up the darkness that haveallowed human activities to continue into the darker and colder hour ofthe hour after sunset. Fire gives human beings the first form of lightand heat to cook food, make tools, have heat to live through cold winterand lighting to see in the dark.

Lighting is now not to be limited just for providing the light we need,but it is also for setting up the mood and atmosphere being created foran area. Proper lighting for an area needs a good combination ofdaylight conditions and artificial lights. There are many ways toimprove lighting in a better cost and energy saving. LED lighting, asolid-state lamp that uses light-emitting diodes as the source of light,is a solution when it comes to energy-efficient lighting. LED lightingprovides lower cost, energy saving and longer life span.

The major use of the light emitting diodes is for illumination. Thelight emitting diodes is recently used in light bulb, light strip orlight tube for a longer lifetime and a lower energy consumption of thelight. The light emitting diodes shows a new type of illumination whichbrings more convenience to our lives. Nowadays, light emitting diodelight may be often seen in the market with various forms and affordableprices.

After the invention of LEDs, the neon indicator and incandescent lampsare gradually replaced. However, the cost of initial commercial LEDs wasextremely high, making them rare to be applied for practical use. Also,LEDs only illuminated red light at early stage. The brightness of thelight only could be used as indicator for it was too dark to illuminatean area. Unlike modern LEDs which are bound in transparent plasticcases, LEDs in early stage were packed in metal cases.

In 1878, Thomas Edison tried to make a usable light bulb afterexperimenting different materials. In November 1879, Edison filed apatent for an electric lamp with a carbon filament and keep testing tofind the perfect filament for his light bulb. The highest melting pointof any chemical element, tungsten, was known by Edison to be anexcellent material for light bulb filaments, but the machinery needed toproduce super-fine tungsten wire was not available in the late 19thcentury. Tungsten is still the primary material used in incandescentbulb filaments today.

Early candles were made in China in about 200 BC from whale fat and ricepaper wick. They were made from other materials through time, liketallow, spermaceti, colza oil and beeswax until the discovery ofparaffin wax which made production of candles cheap and affordable toeveryone. Wick was also improved over time that made from paper, cotton,hemp and flax with different times and ways of burning. Although not amajor light source now, candles are still here as decorative items and alight source in emergency situations. They are used for celebrationssuch as birthdays, religious rituals, for making atmosphere and as adecor.

Illumination has been improved throughout the times. Even now, thelighting device we used today are still being improved. From theillumination of the sun to the time when human can control fire forproviding illumination which changed human history, we have beenimproving the lighting source for a better efficiency and sense. Fromthe invention of candle, gas lamp, electric carbon arc lamp, kerosenelamp, light bulb, fluorescent lamp to LED lamp, the improvement ofillumination shows the necessity of light in human lives.

There are various types of lighting apparatuses. When cost and lightefficiency of LED have shown great effect compared with traditionallighting devices, people look for even better light output. It isimportant to recognize factors that can bring more satisfaction andlight quality and flexibility.

Light devices are widely used in various areas. For some places, theelectricity supply is stable, but this is not true in all areas.

Therefore, it is useful to design a driver circuit that may converts theAC power to a stable driving current used for driving LED modules.

SUMMARY

In some embodiments, a lighting apparatus includes a rectifier, aloading module and a current supplemental module.

The rectifier is connected to an output of the AC power for receiving anAC signal.

The rectifier converts the AC signal to a positive wave signal.

The loading module is disposed at an output of the rectifier.

The loading module includes multiple loading units connected in series.

Output of each loading unit is connected to a current limit module.

Each current limit module has a voltage conductive threshold and aworking cycle dispatched to each current limit module according to thepositive wave signal.

The current supplemental module is connected to an output of therectifier and an input of the loading module.

The current supplemental module charges the current limit module duringthe working cycle and outputs current to the loading module when thepositive wave signal is not sufficient to drive the loading module.

In some embodiments, the input of the current limit module is connectedto an output of the corresponding loading unit and an input of acorresponding next loading unit to form a working loop with thecorresponding loading unit.

In some embodiments, the current limit module includes a current source,a switch unit and a voltage detector.

The current source is series connected the the working loop.

The voltage detector turns on or turns off the switch unit according tovoltage of the working loop.

In some embodiments, the current supplemental module includes a firstcapacitor, an input of the first capacitor is connected between therectifier and the loading module.

In some embodiments, the current supplemental module includes a chargingcurrent source series connected to a back end of the first capacitor.

In some embodiments, the current supplemental module includes acapacitor charging unit with a voltage detector to detect input voltageof the loading module and with a switch unit series connected to a backend of the charging end of the charging current source.

In some embodiments, the voltage detector determines whether to turn onthe switch unit to charge the first capacitor by detecting the inputvoltage of the loading module.

In some embodiments, the current supplemental module includes acapacitor power supply unit with a switch control loop and currentdetector.

The switch control loop is placed between an input of the firstcapacitor and the loading module.

In some embodiments, the current detector detects a passing currentthrough the first loading unit of the series connected loading units todetermine whether to turn on the switch of the switch control loop touse the switch control loop to charge the loading unit.

In some embodiments, the current supplemental module includes a secondcapacitor.

An input of the second capacitor is placed between the rectifier and theloading module.

In some embodiments, the current supplemental module includes aback-to-back NMOS circuit series connected to the second capacitor.

In some embodiments, the current supplemental module includes acapacitor charge-discharge control unit connected to the gate of theback-to-back NMOS circuit to control the back-to-back NMOS circuit.

In some embodiments, the capacitor charge-discharge unit detects apassing current passing through the first loading unit of the seriesconnected loading units.

In some embodiments, the passing current is used to determine turning onor turning off the back-to-back NMOS circuit to respectively charge thesecond capacitor or to use the second capacitor to charge the loadingunit.

In some embodiments, the loading units respectively includes at leastone LED module.

In some embodiments, the AC power is not stable.

In some embodiments, the loading module receives a stable current eventhe AC power is not stable.

In some embodiments, the loading module receives a less-variant currentthan the positive wave signal.

In some embodiments, the loading unit includes a wireless circuit.

In some embodiments, the wireless circuit is further coupled to a thirdcapacitor.

BRIEF DESCRIPTION OF DRAWINGS

FIG. 1 illustrates a circuit architecture diagram of a lightingapparatus embodiment.

FIG. 2 illustrates a circuit example.

FIG. 3 illustrates another circuit example.

FIG. 4 illustrates a working cycle diagram.

FIG. 5 illustrates another working cycle diagram.

FIG. 6 illustrates another working cycle diagram.

DETAILED DESCRIPTION

Driver circuits are important in the design of LED light devices. If thecurrent supplied to the LED modules is not stable, the LED modules areeasily to be damaged or their life spans are significantly affected. Inaddition, people expect LED light devices to emit stable light.

LED modules work in DC (Direct Current) mode. However, most indoor powersource is AC (Alternating Current) mode. Therefore, it is found helpfulto decrease variant of the AC power on driving LED modules.

Please refer to FIG. 1. The lighting apparatus 100 receives an AC power10. The lighting apparatus 100 includes a rectifier 20, a loading module30 and a current supplemental module 40.

The rectifier 20 is connected to a output of the AC power 10 to receivean AC signal. The rectifier 20 converts the AC signal to a positive wavesignal. The rectifier 20 may be a full wave rectifier, a half waverectifier, a bridge rectifier or other similar devices.

The loading module 30 is placed at output of the rectifier 30. Theloading module 30 includes multiple loading units 30A-30C connected inseries. An output of each loading unit is connected to a current limitmodule. Each current limit module has a voltage conductive threshold anda working cycle dispatched to each current limit module based on thepositive wave signal.

The input of each current limit module is connected between an output ofa corresponding loading unit and an input of a corresponding nextloading unit so as to form a working loop with the corresponding loadingunit.

Specifically, the input of the current limit module 31A is connectedbetween the loading unit 30A and next loading unit 30B so as to form afirst ladder loop with the loading unit 30A.

The input of the current limit module 31B is connected between theloading unit 30B and a next loading unit 30C so that to form a secondladder loop with the loading unit 30B.

Similarly, the input of the current limit module 31C is connected to anoutput of the loading unit 30C, or between the loading unit 30C and nextloading unit depending on ladder number, so as to form a third ladderloop with the loading unit 30C.

Each independent ladder loop respectively correspond to a ladder signalstage. In some embodiments, the loading units 30A-30C respectivelyinclude one or more LED modules connected in series or in parallel. Inother words, each loading unit may be a single LED light source ormultiple LED light sources connected in various combination like seriesconnected.

The current limit module 31A includes a current source 311A, a switchunit 312A and a voltage detector 313A. The current source 311A is seriesconnected and placed on the corresponding working loop. The voltagedetector 313A turns on or turns off the switch unit 312A according tothe voltage of the working loop.

The current limit module 31C includes a current source 311C, a switchunit 312C and a voltage detector 313C. The voltage detector 313C turnson or turns off the switch unit 312 according to the voltage of theworking loop.

In the drawings, there are three loading units and three current limitmodules corresponding to three-ladder wave. However, the loading unitand the current limiting module may be any number, e.g. two, four ormore than four.

When there are more loading units and corresponding current limitmodules, the ladder number may be increased.

The current supplemental module is connected to output of the rectifier20 and input of the loading module 30. The current supplemental moduleincludes a charging status for working cycles of any current limitmodule. The current supplemental module may also include output currentto the loading module when the positive wave signal is not sufficient todrive the loading module 30.

The time period that the positive wave signal is at a valley bottomsegments, e.g. Ttr in FIG. 4, in the positive wave signal is referred asthe time period not sufficient to drive the loading module 30.

In some embodiments, the current supplemental module 40 includes a firstcapacitor 41, a charging current source 42, a capacitor charging unit 43and a capacitor power supply unit 44. An input of the first capacitor 41is connected between the rectifier 20 and the loading module 30. Thecharging current source is connected to the back end of the firstcapacitor 41.

The capacitor charging unit 43 includes a voltage detector 431 and aswitch unit 432. The voltage detector 431 is used for detecting an inputvoltage of the loading module 30. The switch unit 432 is seriesconnected at the back end of the charging current source 42.

The voltage detector 431 determines whether to turn on the switch unit432 to charge the first capacitor 41 according to input voltage of theloading module in its working cycle. The capacitor power supply unit 44includes a switch control loop 441 between an input of the firstcapacitor 41 and the loading unit 30A and includes a current detector442.

The current detector 442 detects a passing current (current Ith1) of thecurrent limit module 31A series connected to the first loading unit(loading unit 30A), and determines whether to turn on the switch 4411 ofthe switch control loop 441 so as to use the control loop 441 to supplypower to the loading unit 30A. In some embodiments, more than oneloading units, e.g. loading units 30A-30C, may be supplied withelectricity at the same time, too.

FIG. 3 shows a second embodiment by modifying the current supplementalmodule 40.

For example, the current supplemental module 50 includes a secondcapacitor 51, a back-to-back NMOS circuit and a capacitorcharging-discharging control unit. The input of the second capacitor 51is connected between the rectifier 20 and the loading unit 30A.

The back-to-back NMOS circuit and the second capacitor 51 are connectedin series. The ground is placed between the back-to-back NMOS circuitand the second capacitor 51. The capacitor charging-discharging controlunit is connected to the gate of the back-to-back NMOS circuit tocontrol the turn-on or turn-off of the back-to-back NMOS circuit.

The capacitor charging-discharging control unit also detects a passingcurrent (Ith1) of the current limit module 31A corresponding to thefirst loading unit (the loading unit 30A). The back-to-back NMOS circuitis turned on or turned off according to the passing current to chargethe second capacitor 51 or to use the second capacitor 51 to charge theloading unit 30A.

In some embodiments, more than one loading units may be charged at thesame time.

The current supplemental module 50 includes the second capacitor 51, thecharging control module 52 and the power supply control module 53. Theinput of the second capacitor 51 is connected between the rectifier 20and the loading unit 30A.

The back-to-back NMOS circuit is a charging control module 52. Thecharging control module 52 includes a first voltage detector 521, afirst control switch 522 and a first current source 523. The input andoutput of the second capacitor 51 are respectively connected to twoinputs of the first voltage detector 521. The output of the firstvoltage detector 521 is connected the gate of the first control switch522 to turn on or to turn off the first control switch 522.

The capacitor charging-discharging unit may be a power supply controlmodule 53. The power supply control module 53 includes a second voltagedetector 531 and as second control switch 532.

The input of the second voltage detector 531 is connected between thepower source 311A and the switch unit 312. The input of the secondvoltage detector 531 is connected to a gate of the second control switch532 to control the turn-on or turn-off of the second control switch 532.

The first control switch 522 and the second control switch 532 areconnected in series. The drain of the first control switch 522 isconnected to the drain of the second control switch 532 to form aback-to-back module. The first current source 532 is series connected tothe loop of the first control switch 522 and the second control switch532.

Regarding the switch mode for charging status, when the first voltagedetector 521 detects that the input voltage reaches a corresponding timeboundary, the first control switch 522 is turned on to charge the secondcapacitor 51 (i.e. the trigger edge E1 in FIG. 4). The charging pathfrom the high voltage to low voltage is the output of the rectifier 20to the second capacitor 51, the second control switch, the first currentsource 523, the first control switch and then to the ground.

When the second capacitor 51 has a voltage (sufficient electricity), thefirst control switch 522 is turned off to finish the charging process.

Regarding the switch of the power supply status, when the second voltagedetector 531 of the power supply control module 53 detects that thepassing current Ith1 of the current limit module 31A drops from a highlevel to a low level or even to zero (i.e. the trigger boundary E2 inFIG. 4), the second control switch 532 is turned on so that the secondcapacitor 51 discharges the loading module. The discharging path fromthe high voltage to low voltage is the second capacitor 51, the loadings(loading units 30A, 30B, 30C) and the ground.

When the second voltage detector 531 of the power supply control moduledetects the passing current Ith1 increases from zero or low level tohigh level, the second control switch 532 is turned off.

Please refer to FIG. 4, FIG. 5 and FIG. 6 which show a relation betweenpositive wave signals and the ladder signal.

The positive wave signal refers to the input voltage after the rectifier20. The ladder signal refers to a current signal corresponding to thepositive wave signal.

In FIG. 4, the ladder signal is triggered separately according to thecurrent limit modules 31A, 31B and 31C. When the ladder signal isincreasing, the current limit module 31A firstly detects the positivewave signal rising to a first threshold voltage Vin1, the current limitmodule 31A turns on the switch to limit the passing current to thecurrent Ith1 (turn off the current limiting module 31B and the currentlimit module 31C).

Meanwhile, the current supplemental module 40 detects that the firstthreshold voltage Vin1 discharging the first capacitor 41 and is turnedoff after a time period or after the charging is full. Then, the currentlimit module 31B detects that the positive wave keeps increasing to thesecond threshold voltage Vint. The current limit module 31B turns on theswitch to limit the passing current to the current Ith2 (turn off thecurrent limit module 31A and the current limit module 31C).

Finally, the current limit module 31C detects that the positive wavesignal rises to the third threshold voltage level Vin3, the currentlimit module 31 turns on the switch to limit the passing current to thecurrent Ith3 (turn off the current limit module 31A and the currentlimit module 31B).

When the ladder signal decrease, the current limit module 31B detectsthe positive wave signal lowers down to reach the third thresholdvoltage Vin3, the current limit module 31B turns off the switch so thatthe current lowers to the current Ith2 (current limit module 31A and thecurrent limit module 31C are turned off).

In some embodiments, as shown in FIG. 5, in addition to charge the firstcapacitor with the current supplemental module 40, the first capacitor41 may still be charged in other working cycle.

In some embodiments, as shown in FIG. 6, in addition to charge the firstcapacitor 41 with the supplemental current module 400, the firstcapacitor 41 may also be charged during lowering down.

The design implements a full cycle current supply to loading units toprevent blinking or signal variant problems to enhance quality of LEDlight devices.

In some embodiments, a lighting apparatus includes a rectifier, aloading module and a current supplemental module.

The rectifier is connected to an output of the AC power for receiving anAC signal.

The rectifier converts the AC signal to a positive wave signal.

The loading module is disposed at an output of the rectifier.

The loading module includes multiple loading units connected in series.

Output of each loading unit is connected to a current limit module.

Each current limit module has a voltage conductive threshold and aworking cycle dispatched to each current limit module according to thepositive wave signal.

The current supplemental module is connected to an output of therectifier and an input of the loading module.

The current supplemental module charges the current limit module duringthe working cycle and outputs current to the loading module when thepositive wave signal is not sufficient to drive the loading module.

In some embodiments, the input of the current limit module is connectedto an output of the corresponding loading unit and an input of acorresponding next loading unit to form a working loop with thecorresponding loading unit.

In some embodiments, the current limit module includes a current source,a switch unit and a voltage detector.

The current source is series connected the the working loop.

The voltage detector turns on or turns off the switch unit according tovoltage of the working loop.

In some embodiments, the current supplemental module includes a firstcapacitor, an input of the first capacitor is connected between therectifier and the loading module.

In some embodiments, the current supplemental module includes a chargingcurrent source series connected to a back end of the first capacitor.

In some embodiments, the current supplemental module includes acapacitor charging unit with a voltage detector to detect input voltageof the loading module and with a switch unit series connected to a backend of the charging end of the charging current source.

In some embodiments, the voltage detector determines whether to turn onthe switch unit to charge the first capacitor by detecting the inputvoltage of the loading module.

In some embodiments, the current supplemental module includes acapacitor power supply unit with a switch control loop and currentdetector.

The switch control loop is placed between an input of the firstcapacitor and the loading module.

In some embodiments, the current detector detects a passing currentthrough the first loading unit of the series connected loading units todetermine whether to turn on the switch of the switch control loop touse the switch control loop to charge the loading unit.

In some embodiments, the current supplemental module includes a secondcapacitor.

An input of the second capacitor is placed between the rectifier and theloading module.

In some embodiments, the current supplemental module includes aback-to-back NMOS circuit series connected to the second capacitor.

In some embodiments, the current supplemental module includes acapacitor charge-discharge control unit connected to the gate of theback-to-back NMOS circuit to control the back-to-back NMOS circuit.

In some embodiments, the capacitor charge-discharge unit detects apassing current passing through the first loading unit of the seriesconnected loading units.

In some embodiments, the passing current is used to determine turning onor turning off the back-to-back NMOS circuit to respectively charge thesecond capacitor or to use the second capacitor to charge the loadingunit.

In some embodiments, the loading units respectively includes at leastone LED module.

In some embodiments, the AC power is not stable.

In some embodiments, the loading module receives a stable current eventhe AC power is not stable.

In some embodiments, the loading module receives a less-variant currentthan the positive wave signal.

In some embodiments, the loading unit includes a wireless circuit.

In some embodiments, the wireless circuit is further coupled to a thirdcapacitor to further removing noises in the wireless signal.

The foregoing description, for purpose of explanation, has beendescribed with reference to specific embodiments. However, theillustrative discussions above are not intended to be exhaustive or tolimit the invention to the precise forms disclosed. Many modificationsand variations are possible in view of the above teachings.

The embodiments were chosen and described in order to best explain theprinciples of the techniques and their practical applications. Othersskilled in the art are thereby enabled to best utilize the techniquesand various embodiments with various modifications as are suited to theparticular use contemplated.

Although the disclosure and examples have been fully described withreference to the accompanying drawings, it is to be noted that variouschanges and modifications will become apparent to those skilled in theart. Such changes and modifications are to be understood as beingincluded within the scope of the disclosure and examples as defined bythe claims.

1. A lighting apparatus connected an AC power, comprising: a rectifierconnected to an output of the AC power for receiving an AC signal,wherein the rectifier converts the AC signal to a positive wave signal;a loading module, disposed at an output of the rectifier, wherein theloading module comprises multiple loading units connected in series,wherein output of each loading unit is connected to a current limitmodule, wherein each current limit module has a voltage conductivethreshold and a working cycle dispatched to each current limit moduleaccording to the positive wave signal; and a current supplemental moduleconnected to an output of the rectifier and an input of the loadingmodule, wherein the current supplemental module charges the currentlimit module during the working cycle and outputs current to the loadingmodule when the positive wave signal is not sufficient to drive theloading module.
 2. The lighting apparatus of claim 1, wherein the inputof the current limit module is connected to an output of thecorresponding loading unit and an input of a corresponding next loadingunit to form a working loop with the corresponding loading unit.
 3. Thelighting apparatus of claim 2, wherein the current limit modulecomprises a current source, a switch unit and a voltage detector,wherein the current source is series connected the the working loop,wherein the voltage detector turns on or turns off the switch unitaccording to voltage of the working loop.
 4. The lighting apparatus ofclaim 1, wherein the current supplemental module comprises a firstcapacitor, an input of the first capacitor is connected between therectifier and the loading module;
 5. The lighting apparatus of claim 4,wherein the current supplemental module comprises a charging currentsource series connected to a back end of the first capacitor.
 6. Thelighting apparatus of claim 5, wherein the current supplemental modulecomprises a capacitor charging unit with a voltage detector to detectinput voltage of the loading module and with a switch unit seriesconnected to a back end of the charging end of the charging currentsource.
 7. The lighting apparatus of claim 6, wherein the voltagedetector determines whether to turn on the switch unit to charge thefirst capacitor by detecting the input voltage of the loading module. 8.The lighting apparatus of claim 7, wherein the current supplementalmodule comprises a capacitor power supply unit with a switch controlloop and current detector, wherein the switch control loop is placedbetween an input of the first capacitor and the loading module.
 9. Thelighting apparatus of claim 8, wherein the current detector detects apassing current through the first loading unit of the series connectedloading units to determine whether to turn on the switch of the switchcontrol loop to use the switch control loop to charge the loading unit.10. The lighting apparatus of claim 1, wherein the current supplementalmodule comprises a second capacitor, wherein an input of the secondcapacitor is placed between the rectifier and the loading module. 11.The lighting apparatus of claim 10, wherein the current supplementalmodule comprises a back-to-back NMOS circuit series connected to thesecond capacitor.
 12. The lighting apparatus of claim 11, wherein thecurrent supplemental module comprises a capacitor charge-dischargecontrol unit connected to the gate of the back-to-back NMOS circuit tocontrol the back-to-back NMOS circuit.
 13. The lighting apparatus ofclaim 12, wherein the capacitor charge-discharge unit detects a passingcurrent passing through the first loading unit of the series connectedloading units.
 14. The lighting apparatus of claim 13, wherein thepassing current is used to determine turning on or turning off theback-to-back NMOS circuit to respectively charge the second capacitor orto use the second capacitor to charge the loading unit.
 15. The lightingapparatus of claim 1, wherein the loading units respectively comprisesat least one LED module.
 16. The lighting apparatus of claim 1, whereinthe AC power is not stable.
 17. The lighting apparatus of claim 16,wherein the loading module receives a stable current even the AC poweris not stable.
 18. The lighting apparatus of claim 17, wherein theloading module receives a less-variant current than the positive wavesignal.
 19. The lighting apparatus of claim 1, wherein the loading unitcomprises a wireless circuit.
 20. The lighting apparatus of claim 19,wherein the wireless circuit is further coupled to a third capacitor.